DENVER – “Pull the trigger,” John Elway told his Denver Broncos star, Tim Tebow, trying to shake the quarterback from a three-game funk.

Tebow went one better — he pulled off an upset.

A rejuvenated Tebow connected with Demaryius Thomas on an electrifying 80-yard touchdown pass on the first play of overtime and the Broncos defeated the stunned Pittsburgh Steelers 29-23 in the AFC wild-card game on Sunday. The Broncos next play the Patriots Saturday night in Foxborough, Mass.

Wild doesn’t begin to describe the winning TD. The play took 11 seconds and was the quickest ending to an overtime in NFL history.

Thomas hauled in a high play-action pass at Denver’s 38, stiff-armed Ike Taylor and then outraced backup safety Ryan Mundy to the end zone.

“I was just saying, ‘Man trust your speed. Trust your speed. Don’t cut back. Don’t cut back.’ And he kept it straight. He outran the guy,” said Willis McGahee, whose fourth-quarter fumble helped Pittsburgh tie it.

“I was like ‘Oh my God, is he still running?’ Please just go. Please. Please.”

Tebow, who looked as startled as everyone else, chased down Thomas and knelt on one knee — Tebowing as it’s known — in the end zone. Then he pounded a fist in triumph and took a victory lap.

“When I saw him scoring, first of all, I just thought, ‘Thank you, Lord,”‘ Tebow said. “Then, I was running pretty fast, chasing him — like I can catch up to D.T! Then I just jumped into the stands, first time I’ve done that. That was fun. Then, got on a knee and thanked the Lord again and tried to celebrate with my teammates and the fans.”

Behind Tebow’s 316 yards passing, the Broncos (9-8) are heading to New England for a second-round game against the top-seeded Patriots.

And, unlike Elway, who lost his first postseason start — to the Steelers at home in 1984 — Tebow is 1-0 in the playoffs.

“We’re just a fighting team. A lot of resilience,” cornerback Champ Bailey said. “In any adverse situation, we’ll find a way to get out of it. Everybody says we backed into the playoffs, we’re in. We did something right along the way. We’re in it. We won a game. Now, we’ve got to go try to win another one.”

The Steelers (12-5) lost despite Ben Roethlisberger rallying injury-depleted Pittsburgh from a two-T halftime deficit with 10 points in the final 10 minutes.

Pittsburgh called tails for the overtime coin toss, and it came up heads.

Tebow, who engineered five fourth-quarter comebacks and three OT wins in the regular season, wasted no time finding Thomas to end the game.

“They were the No. 1 defense and we are the No. 1 offense running the ball,” Thomas said. “So, I feel like they wanted to make a statement and stop the run. I don’t know if they forgot about the passing game. The last couple of games that we had, we were not passing the ball that great.”

Thus, Elway’s admonition.

“He showed he’s a quarterback in the NFL, case closed,” McGahee said. “They say he couldn’t throw. They said we wouldn’t be able to run the ball on them. We did that. I wonder what they’re going to say next week.”

Mundy was playing in place of Ryan Clark, the Steelers’ leading tackler who sat out because of a blood condition that’s exacerbated at altitude.

Clark was one of several Steelers sidelined or injured. Pro Bowl center Maurkice Pouncey was out, replaced by Doug Legursky, who had a bad snap right before halftime that moved Pittsburgh out of field-goal range.

Thomas raced down the Broncos’ sideline, sending the crowd, including Elway, the Broncos’ executive vice president, into a frenzy at Sports Authority Field.

And Elway, the architect of so many of those magical moments at the old place, celebrated on the field like he used to when he was the one engineering the triumphs.

The Patriots walloped the Broncos 41-23 last month, sending Tebow into a funk that included seven turnovers and a 40 percent completion clip — and prompting Elway to implore him to “pull the trigger” in the playoffs.

Did he ever.

Tebow completed 10 of 21 passes but Thomas hauled in four of them for 204 yards after his top target, Eric Decker, was lost to a left knee injury on the first play of the second quarter when he was hit by linebacker James Harrison.

Tebow threw two touchdown passes and also ran 10 times for 50 yards and a TD.

Making his first appearance in the playoffs after going 7-4 as Denver’s starter, Tebow outplayed Roethlisberger, a two-time Super Bowl winner playing on a bad ankle, who fell to 10-4 in the playoffs.

Roethlisberger was 22 for 40 for 289 yards with one TD, one interception and five sacks.

The Broncos snapped a three-game losing streak that had many wondering if they were even worthy of their first playoff in six seasons, and it kept the Steelers from their 34th playoff win, which would have broken a tie with the Cowboys for the most ever.

Tebow led Denver to 20 second-quarter points — they had scored just 13 in the quarter in his 11 starts — but a 20-6 halftime lead didn’t last long.

Receiver Mike Wallace had a 1-yard TD run, Shaun Suisham kicked a short field goal and Jerricho Cotchery grabbed a 31-yard TD pass with 3:48 left in regulation to tie it.

The Steelers were nearing field goal range in the final minute of regulation but the Broncos sacked Roethlisberger three times on that final drive, forcing a fumble that Roethlisberger recovered.

“We were moving it and we had a shot,” Roethlisberger said. “Someone got, it felt like a finger, on the ball and knocked it out. After that, you’re trying to throw a 70-yard Hail Mary and that’s hard.”